The present invention relates to a new and improved construction of lift or elevator landing door frame arrangement.
In its more specific aspects, the present invention concerns a new and improved lift landing door frame arrangement comprising a door frame which contains an upright at each side thereof, a respective horizontally adjustable lateral caulking or sealing element is arranged at each one of the uprights, a vertically adjustable top caulking or sealing element is arranged at the upper or topside of the door frame, said caulking or sealing elements being structured to adapt the door frame to the outline or contour of a landing opening in a lift or elevator shaft.
In order to compensate for relative inaccuracies which, at the time of construction of a building, inevitably occur at the landing openings formed at the lift shaft or chute in order to accommodate the landing doors, it is usual to provide landing openings of sufficient size to permit placement or mounting of a lift landing door frame arrangement. Such lift landing door frame arrangement is usually constituted by a door frame with relatively narrow, laterally finished uprights and at its upper or topside by caulking or sealing elements adaptable to the outline of the related landing opening. Retouching or masonry joinings or joints are thus avoided to a large extent. In numerous cases, such solution is imposed by the fact that, with the aim of lowering the costs of construction and/or achieving standardization, certain architects or contractors refuse to consider lift or elevator shafts including masonry returns at the landing openings as well as performing retouching of the masonry once the landing door frame arrangement has been installed.
In a lift landing door frame arrangement as known, for example, from French Pat. No. 2,120,596, caulking elements are utilized to effect lateral caulking along the height of the door frame, the lateral caulking elements forming two sheet metal elements bent to form a U-shape in cross-section. The caulking elements also partially cover the front surface of the related door frame upright to which the caulking element is associated. At their rear, the caulking elements are connected to the related upright by means of fixing tongues. At its outer edge, each bent sheet metal element is completed by a horizontal adjustable angle iron which can be connected to the rear of the caulking element by means of bolts. A pediment is fixed above an upper crosspiece of the door frame and extends over the entire width of the door frame arrangement. A vertically adjustable caulking plate is arranged at the rear of the pediment. Lateral caulking above the angle irons is effected by means of horizontally adjustable sheet metal squares fixed to the extremities of the pediment.
The known lift landing door frame arrangement has the inconvenience of requiring for the lateral as well as for vertical caulking, the use of different kinds of elements and, consequently, a large number of fixing means. The construction, therefore, is relatively complicated. Another inconvenience is yet based on the fact that unless the pediment and the vertical caulking plate are positionally arranged to adjust for the width of the landing opening in the shaft, gaps will exist in the landing door frame arrangement adjacent the sheet metal squares fixed to the extremities of the pediment. Such gaps, particularly those existing at the junctions of the different caulking elements, must be sealed by connecting elements made of rubber or similar material. Even then, this known lift landing door frame arrangement requires additional measures to satisfy existing regulations in respect of water tightness and fire resistance of lift shafts and landing doors of lifts or elevator equipment which are in force in certain countries. Finally, the narrowness of the visible surface of the angle irons, which arises upon contraction of the bent sheet metal elements forming the lateral caulking elements, may vary from one side of the door frame to the other and/or from one lift landing door frame arrangement to the other and such eye-catching variations have the disadvantage of making the width inaccuracies in the landing openings of the lift shaft clearly stand out.